Railway truck bolster dampener



Aug. 20, 1968 1.. CARDWELL RAILWAY TRUCK BOLSTER DAMPENER 2 Sheets-Sheet 1 Filed Aug. 9. 1966 INVENTOR CARDWELL LLOYD BY% {5W1 ATT'YS.

1968 CARDWELL RAILWAY TRUCK BOLSTER .DAMPENER 2 Sheets-Sheet 2 Filed Aug. 9, 1966 INVENTOR CARDWE L 3% W LLOYD ATT Y5.

United States Patent 3,397,652 RAILWAY TRUCK BOLSTER DAMPENER Lloyd Cardwell, Chicago, Ill., assignor to Cardwell Westinghouse Company, a corporation of Delaware Filed Aug. 9, 1966, Ser. No. 571,310

19 Claims. (Cl. 105193) ABSTRACT OF THE DISCLOSURE Railroad car sidesway is counteracted without interfering with vertical motion of the car by connecting each side frame of the car truck to the bolster through linkage which in turn is connected to an energy absorption and dissipation device in such manner that the device counteracts sidesway without counteracting vertical motion of the car.

This invention relates to apparatus and process for preventing sidesway or roll of railway cars, particularly heavy high center of gravity freight cars.

In recent years, railway freight cars of greater length and higher center of gravity capable of carrying heavier loads, have been put into service on the nations railroads. These cars are generally supported by trucks at either end, the car body resting on the truck bolster, which in turn is supported by spring nests mounted on the truck side frame. The purpose of the spring nest is to prevent vertical shock to the car and to the car lading in order to prevent damage thereto. While the springs in combination with friction dampening devices are effective in mitigating vertical shock, they are not eifective in counteracting sidesway, since, if sufficient friction is used in the spring nests and dampening devices to counteract sidesway, it will limit vertical movement to such an extent that vertical shock to the car and lading will cause damage. The natural frequency of the spring nest on which the truck bolster is mounted is about 150 cycles per minute, and hence the truck springs are ineffective to prevent overturning of the car.

High volume freight cars with truck centers approximating the rail length have a tendency to sway when the natural frequency of a loaded car, which is about 30 cycles per minute, coincides with the frequency of the rail joints over which the cars are passing. As a result, numerous wrecks occur from overturning cars.

It has been proposed in the prior art to counter-act lateral vibration of sidesway of railroad cars by utilizing the amplitude of sidesway to actuate an electric circuit which in turn controls relay-actuated valves which in turn control a hydraulic snubbing arrangement. One such system is disclosed in Schoepf et al. Patent No. 135,224, in which a pendulum-type switch is used to activate the electrical circuit. A somewhat similar system is disclosed in Schoepf et 21]. Patent 2,161,687, in which a U-tube mercury switch is used to actuate the system. Such systems are complicated, expensive, and have not been found to be practical.

The present invention involves a relatively simple mechanical lever arrangement connected to an energy absorption type device which permits vertical movement of the car and bolster without interfering therewith, as long as the bolster and car remain level. However, when the bolster vibrates or sway laterally, the lever mechanism exerts a counteracting effect on the bolster to prevent or mitigate sidesway, rolling, or vibration of the car. By reason of the manner in which the lever mechanism is attached to the energy absorption device, it is possible to accomplish the desired result by the use of a simple mechanical arrangement.

In accordance with my invention, a lever mechanism is fastened to the bolster between the center and one end thereof, and a second lever mechanism is fastened to the 3,397,652 Patented Aug. 20, 1968 bolster between the center and the other end thereof. The lever mechanisms are then attached to an energy absorption device in such a manner that the two mechanisms will exert no force on the device so long as the car and bolster move up and down in a straight vertical direction. However, if sidesway or rolling of the car occurs, the lever mechanisms on each side of the bolster co-act to produce opposing forces on the device, thereby tending to restrain the lateral movement of the car.

An object of this invention is to provide means for counteracting sidesway and roll in railroad cars. A further object of the invention is to provide means for counteracting sides-way and roll in railroad cars without interfering with the vertical movement thereof. Still another object of the invention is to provide mechanical linkage operatively connected to an energy absorption device which will counteract railroad car sidesway or roll without affecting the vertical motion of the car. A still further object of the invention is to provide rail road cars equipped with devices as aforesaid, which will prevent roll or sidesway without disturbing the vertical movement of the car. Another object of the invention is to provide a method for mitigating railroad car sidesway or roll without interfering with the vertical motion of the car.

These and other objects of the invention will manifest themselves from the following description and drawings, of which FIGURE 1 is a diagrammatic elevational view of a freight car truck showing the manner in which the novel means for counteracting sidesway roll is mounted there- FIGURE 2 is a perspective view of a railroad car truck embodying the invention, looking upwardly at the bottom of the truck;

FIGURE 3 is an end elevational view of the linkage forming a part of the invention;

FIGURE 4 is a cross-sectional view of one form of energy absorption and dissipation device which may be used as part of my invention;

FIGURE 5 is another modification of an energy absorption dissipation device which may be used as part of my invention; and

FIGURE 6 is still another modification of energy absorption device which may be used as part of my invention.

Referring to the drawings, numeral 1 represents a bolster supported on the spring nests 3, mounted on the side frames 5 and 7 of a railroad car truck. Lugs or ears 9 are mounted by welding, or formed integrally, on the bottom of the bolster 1, a pair of lugs being mounted on each side of the center of the bolster, preferably as close to the ends thereof as is (feasible. One end of a straight link 11 is pivotally fastened to the lugs on each side of the center of the bolster by means of pins 13. The other end 15 of the link 11 is forked in order to pivotally receive one end 16 of a bell crank 17. The end 16 of the bell crank is pivotally mounted by means of the pin 19. The other end 21 of the bell crank 17 is forked. The center of the bell crank is pivotally mounted by means of pin 22 between the lugs 23, extending upwardly from the rack 25 which is rigidly mounted between the lower portion of the side frames 5 and 7, immediately below the bolster. Rack 25 is preferably mounted between the side frames by means of bolts 27 passing through holes in the end of rack 25 and through holes in the ears of lugs 29, extending inwardly from the side frame.

The forked end 21 of the bell crank on the left hand side of the bolster is pivotally fastened by means of pin 31 to the end of rod 33. The forked end of the bell crank on the right side of the bolster is pivotally fastened by pin 34 to clevis 35.

Referring more particularly to FIGURE 4, the rod 33 is formed with a collar 37 which loosely fits in an opening 39 in one end of cylinder 41. The other end of the rod has a nut threadedly mounted thereon. Adjacent the collar 37 is spring follower 45 and adjacent nut 43 is spring follower 47. Between spring followers 45 and 47 is mounted a rubber spring 49 and a coil spring 51. Welded to the other end of the cylinder 41 is a short hollow cylinder 53 which fits snugly within cylinder 41 and acts as a stop for spring follower 47. The end 55 of the cylinder acts as a stop for spring follower 45. Clevis 35 is welded to the outer end of hollow cylinder 53. Cylinder 41 is sli-dably supported on rack 25. The rubber spring 49 and coil spring 51 function as an energy absorption and dissipation device in the manner of the device shown and described in US. Patent 3,178,036 of Lloyd Cardwell.

An alternative form of energy absorption and dissipation device is shown in FIGURE 5. Between the ends of the rod 33 is formed an enlarged portion 57 which snugly and slidably fits in clylinder 59. Enlarged portion 57 is recessed to receive piston ring 61 in order to avoid any sub stantial leakage of fluid as the rod slides back and forth in the cylinder 59. The large portion or piston 57 is formed with orifices 63 and 65 which are preferably spring controlled such as that shown in FIGURES 11 to 13 of US. Campbell et a1. Patent No. 3,150,782 to operate in opposite directions so as to meter flow of hydraulic fluid through the piston 57 in either direction. The end 67 is formed with a bearing surface in which the rod 33 slides and with suitable packing glands 69 to prevent leakage of fluid. The end 67 is welded to the cylinder 59 as shown at 71. A hollow cylinder 73 having a closed end 75 and an open end 77 is welded to the other end of cylinder 59. Cylinder 73 fits snugly within cylinder 59. The end 75 is formed with a bearing surface in which the inner end 79 of rod 33 can slide. It also contains suitably packing glands 81 in order to prevent leakage of fluid from the cylinder 59. The rod 33 and the clevis 35 are connected to the bell cranks on the left and right side of the bolster in the same manner as described in connection with FIGURE 4.

Another form of energy absorption and dissipation device is shown in FIGURE 6-. In this form of device, two elastomeric units 83 and 85 are bonded or vulcanized to rings 87 and 89, respectively, mounted snugly in cylinder 91. The rings 87 and 89 are separated by spacer ring 93 and are held in cylinder 91 by means of retainers 95 and 97 welded to the ends of the cylinder. The elastomeric units 83 and 85 are also bonded to rods 99 and 101, respectively. Each rod is provided with a clevis or other means at its outer end to be fastened to linkage on the same side in the same manner as previously described with respect to the rods and cylinders of FIGURES 4 and 5.

The device operates as follows:

When the bolster 1 on which the car body is mounted vibrates or moves in a straight vertical direction, the linkage on the left hand side of the bolster causes the rod 33 to move in the same direction as the linkage on the right side causes the cylinder 41 (FIGURE 4) or cylinder 59 (FIGURE to move. When the bolster moves upwardly, the linkage on the left side will cause the rod to move toward the right. Similarly, the linkage on the right side will cause the cylinder 41 or 59 to move to the right. Since the linkages on the right and left side are identical, they will cause identical movement of the rod and cylinder, and as a result the linkage and energy absorption and dissipation device will not oppose the upward motion of the bolster. Similarly, when the bolster moves directly vertically downward, the linkage on the left side will cause the rod 33 to move toward the left and the linkage on the right will cause the cylinder 41 or 59 also to move to the left in unison with the rod and therefore will have no effect on the movement of the bolster.

On the other hand, if the bolster vibrates so as to cause the car to roll or sway from side to side, the linkage and the connecting force absorption and dissipation device will become effective. If the left side of the bolster moves upward while the right side of the bolster moves downward, the linkage on the left side will force the rod to the left while the linkage on the right side will force the cylinder to the right. The device shown in FIGURE 4, collar 37, presses against spring follower 45, and the inner ends of cylinder 53- press against spring 51, thereby setting up a resistance to the swaying motion of the car.

If the car and bolster tends to sway in the opposite direction so that the left side of the bolster moves downwardly and the right side moves upwardly, then the linkage on the left side will act to force the rod 33 to the left and the linkage on the right side will act to force the cylinder 41 to the right. In this case the nut 43- acting on spring follower 47 and the cylinder end 55 acting on spring follower 45 will compress the rubber spring 49 and the coil spring 51, thereby setting up force resistance to the swaying movement of the car.

The device shown in FIGURE 5 functions to counteract sidesway or roll in the same manner as the device in FIGURE 4. In the device of FIGURE 5, the cylinder is filled with a hydraulic fluid. Orifices 63 and 65 are designed to control flow of fluid from one side of the piston element 57 to the other. The orifices 63 and 65 may be calibrated orifices or they may be spring controlled to open in opposite directions so that one orifice controls flow in one direction and one controls flow in the other.

The cylinder in FIGURE 6 is free to slide on support rack 25. Thus, when the car and bolster move in a vertical direction, the cylinder 91, rod 99, and rod 101 all move in unison and offer no resistance to the movement of the bolster. But, if the bolster and car sidesway or roll, shear is set up in the two elastomeric units 83 and in opposite directions thereby counteracting the sidesway or roll.

Although I have illustrated only three forms of energy absorption and dissipation devices, it will be evident that other forms may be used, as for example, a pair of pistons mounted in a stationary cylinder, the two pistons being connected by suitable rods to the two sets of linkages and with suitable orifices controlling flow of fluid through the pistons. In a device of this type, it is necessary to provide a storage tank connected to the cylinder in order to accommodate the difference in volume of the operating cylinder when the piston rods move in and out thereof when using substantially incompressible hydraulic fluid. Instead of using a substantially incompressible hydraulic fluid, a compressible fluid such as silicone fluid may be used in a piston-type device without the necessity of providing additional storage space for the fluid to accommodate the difference in volume.

Although I prefer to use an energy absorption and dissipation device as part of the combination, a conservative energy type device, such as a coil spring may be connected between the forked ends of the two bell cranks in order to counteract sidesway or roll.

I claim:

1. Apparatus for counteracting sidesway of railroad cars comprising an energy absorption and dissipation device connected between two rigid members adapted to move reciprocatively, lever means connected to one of said members, separate lever means connected to the other of said members, said lever means being constructed in such manner as to enable them when properly mounted on a railroad car truck, to urge said members in opposite directions upon sidesway of the car, said device being constructed to absorb and dissipate energy resulting from movement of said members toward or away from each other.

2. Apparatus in accordance with claim 1, in which said each lever means includes a substantially straight link adapted to have one end connected to the car truck bolster, a bell crank, one end of which is pivoted to the other end of said link and the center of which is adapted to be pivotally fastened to the car truck side frame, and the other end of the bell crank is operatively connected to one of said members.

3. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 2 in which one end of the straight link of one of said lever means is fastened to the bolster between the center and one end thereof, one end of the straight link of the other of said lever means is connected to the bolster between the center and the opposite end thereof, the center of each bell crank is pivotally fastened to the frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

4. The combination in accordance with claim 3 in which said frame comprises a side frame on each side of said truck, a rigid structure mounted between said side frames below said bolster, said structure having upstanding ears and the center of each bell crank is pivotally fastened to at least one such ear.

5. Apparatus in accordance with claim 1 in which said energy absorption and dissipation device comprises a closed cylinder connected adjacent the inside ends thereof to a storage chamber, a piston rod extending through one end of the cylinder in leakproof sliding relationship with said end and connected to one of said members, a second piston rod extending through the opposite cylinder end in leakproof sliding relationship therewith and connected to the other of said members, a slidable piston mounted on the inside end of each piston rod, said pistons fitting snugly against the cylinder wall, said cylinder being substantially completely filled with hydraulic fiuid when said pistons contact each other, said pistons having orifices to provide a predetermined rate of energy dissipation.

6. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 5, in which one of said lever means is operatively fastened to the bolster between the center and one end thereof and to said frame, the other lever means is operatively fastened to the bolster between the center and the opposite end thereof and to said frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

7. The combination in accordance with claim 6, in which said frame comprises a side frame on each side of said truck, a rigid structure mounted between said side frames below said bolster, said structure having upstanding ears, and each of said lever means is pivotally fastened to at least one such ear.

8. Apparatus in accordance with claim 1 in which said energy absorption and dissipation device comprises a cylinder containing a rubber spring, a rigid plate on each end of said spring, a rod extending through both said plates, an abutting element rigidly mounted on said rod adjacent the outer surface of each plate, means for attaching one end of said rod to one said lever means and means for attaching said cylinder at the end opposite to that of the attached rod end, to said other lever means.

9. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 8, in which one of said lever means is operatively fastened to the bolster between the center and one end thereof and to said frame, the other lever means is operatively fastened to the bolster between the center and the opposite end thereof and to said frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

10. The combination in accordance with claim 9, in which said frame comprises a side frame on each side of said truck, a rigid structure mounted between said side frames below said bolster, said structure having upstanding ears, and each of said lever means is pivotally fastened to at least one such car.

11. Apparatus in accordance with claim 1 in which said energy absorption and dissipation device comprises a closed cylinder, a piston snugly and slidably mounted therein, a hydraulic fluid in said cylinder, orifices passing through said piston to control the rate at which force is dissipated when said piston and cylinder move relative to each other, a rod attached to said piston, means for fastening one end of said rod to one said lever means and means for fastening said cylinder at the end opposite to that of the attached rod end, to said other lever means.

12. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 11, in which one of said lever means is operatively fastened to the bolster between the center and one end thereof, and to said frame, the other lever means is operatively fastened to the bolster between the center and the opposite end thereof and to said frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

13. The combination in accordance with claim 12, in which said frame comprises a side frame on each side of said truck, a rigid structure mounted between said side frames below said bolster, said structure having upstanding ears, and each of said lever means is pivotally fastened to at least one such ear.

14. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 1, in which one of said lever means is operatively fastened to the bolster between the center and one end thereof and to said frame, the other lever means is operatively fastened to the bolster between the center and the opposite end thereof and to said frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

15. The combination in accordance wtih claim 14 in which said frame comprises a side frame on each side of said truck, a rigid structure mounted between said side frames below said bolster, said structure having upstanding ears, and each of said lever means is pivotally fastened to at least one such ear.

16. Apparatus in accordance with claim 1, in which said two members comprise two rods and said energy absorption and dissipation device comprises two elastomeric units, the outer surfaces of which are bonded to a rigid movable member, and a rod bonded to the center portion of each of said units, said rods being movable relative to said rigid movable member.

17. The combination of a railroad car truck, having a spring supported bolster and a frame, with the apparatus defined in claim 16 in which the first mentioned lever means is operatively fastened to the bolster between the center and one end thereof and to said frame, the second mentioned lever means is operatively fastened to the bolster between the center and the opposite end thereof and to said frame and said absorption and dissipation device is mounted to move reciprocatively in the same path as said rigid members.

18. The method of counteracting sidesway in a railroad car subjected to both sidesway and vertical motion comprising mechanically converting the swaying motion on both sides of the car to straight line motion, said motion on one side being in a direction opposite to that on the other side and impressing said opposite straight line motions on an energy absorption and dissipation device in such manner as to counteract sidesway without counteracting vertical motion of the car.

19. The method of counteracting sidesway in a railroad car subjected to both sidesway and vertical motion comprising simultaneously absorbing and dissipating the energy produced by swaying motion on both sides of said car without interfering with the vertical up and down movement of the car body.

(References on following page) References Cited UNITED FOREIGN PATENTS STATES PATENTS 641,915 2/1937 Germany.

619,300 9/1935 Germany. Kmckenberg at 105-499 103,495 6/1917 Great Britain. Baade 105-192 5 Hobson 105- 197 ARTHUR L- LA POINT, Primary Examiner.

Cottrell 105208.2 H. BELTRAN, Assistant Examiner. 

